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Who refills their oxygen at home?

nbachert

Well Known Member
I?m interested in building my own home oxygen transfix system but would like to talk to someone who is doing it. Please pm me or email at rightseat@ Gmail.com

Thanks

Nick
 
I do.

I?m interested in building my own home oxygen transfix system but would like to talk to someone who is doing it. Please pm me or email at rightseat@ Gmail.com

Thanks

Nick

What do you need? It's pretty simple...even I can do it!
 
Aye. We've only been sucking the custom O2 in the airplane for a little over a decade. Not dead yet. Dirt cheap.
 
Having a T of O2 at home for $$$ plus monthly bottle rent vs $5 per fill at the local scuba store?
 
No monthly bottle rent here. Own it outright. Plus no local dive shop with $5 O2 fills. I suppose if there was a dive shop nearby with those prices I'd be in, but having the bulk tank in the hangar sure is convenient!
 
I bought a used homedics oxygen generator and compressor. A few modifications to the connector so it would work with standard medical fittings and it works great! $500 on craigslist. I'm not sure how commonly available they are though.
 
FWIW

On a related note, I purchased a used Inogen G2 portable oxygen concentrator locally off craigslist for something like $1k including 3 batteries. A machine not to refill tanks but rather to produce concentrated oxygen on-the-fly (as it were).

I've only used solo at a max altitude of 15k but the machine kept up. Google says weight is 7.25 pounds with one battery (can run off 12v). Very compact and convenient.
 
On a related note, I purchased a used Inogen G2 portable oxygen concentrator locally off craigslist for something like $1k including 3 batteries. A machine not to refill tanks but rather to produce concentrated oxygen on-the-fly (as it were).

I've only used solo at a max altitude of 15k but the machine kept up. Google says weight is 7.25 pounds with one battery (can run off 12v). Very compact and convenient.

I have researched the use of a concentrator years ago, and like most conversations there are mixed results/opinions. Have there been any recent advances in using a concentrator for aviation?
 
On a related note, I purchased a used Inogen G2 portable oxygen concentrator locally off craigslist for something like $1k including 3 batteries. A machine not to refill tanks but rather to produce concentrated oxygen on-the-fly (as it were).

I've only used solo at a max altitude of 15k but the machine kept up. Google says weight is 7.25 pounds with one battery (can run off 12v). Very compact and convenient.

Do you use a pulse-oximeter? I'd be curious what levels you were able to maintain at altitude.
 
I'm not familiar with the generational technology in the concentrators (it looks like Inogen is up to a G4 and I've got a G2).

I don't know why they would have a bad reputation. I went through some courses at CAMI a couple years ago in OKC where the subject came up; I would characterize those discussions as the same I've had everywhere else--no one has any practical real-world experience and no opinion other than curiosity. I have to say that I've not personally heard a negative review/anectdotal experience with a concentrator. The device will tell you if it is not delivering what you are asking of it with very high fidelity.

Why am I limited to 15,000 feet? It's simply as high as I've gone (currently flying a spam can and 15k is an event requiring months of planning and effort). :)
 
Do you use a pulse-oximeter? I'd be curious what levels you were able to maintain at altitude.

I do use a fingertip pulse-ox (Walmart $25). I've done a fair amount of observation over the years. My pulse goes up at a fairly low altitude, with saturations dropping below baseline well under 10k feet. On supplemental O2, pulse/saturation remain baseline as high as I've gone (15k). I fly almost exclusively solo and since buying the machine I routinely use it during the daytime if I'm going on really any cross country, regardless of altitude (assuming more than 4-5k above home ground level). I've not flown at night in quite a while but would use the machine at night quite liberally. It's quite convenient.
 
I tested a couple of concentraters a few years back, and they worked great. I think the only reason they don’t make headway versus bottled O2 in our community is that the cost, and the fact that you need one for each person (which costs even more). When you do the math, you can buy a LOT of bottled O2 before you reach a break even point, given that most people aren’t using them all day every day when they fly (like folks do for medical purposes).

I really like them but couldn’t justify the cost - even for a refurb.

And yes - I do my own bottle refills from a big tank in my hangar.
 
I do use a fingertip pulse-ox (Walmart $25). I've done a fair amount of observation over the years. My pulse goes up at a fairly low altitude, with saturations dropping below baseline well under 10k feet. On supplemental O2, pulse/saturation remain baseline as high as I've gone (15k). I fly almost exclusively solo and since buying the machine I routinely use it during the daytime if I'm going on really any cross country, regardless of altitude (assuming more than 4-5k above home ground level). I've not flown at night in quite a while but would use the machine at night quite liberally. It's quite convenient.

This makes for some good objective evidence that makes me thing any bad reputation the concentrators have is probably related to early technology, the high cost, or possibly just wrong... $1k per person does make me pause at jumping on board with this approach.

Thanks!
Don
 
Been filling my own O2 tank for past 8 years from large O2 bottle that I bought from local welding supply. Entire refill setup including buying the tank was less than $250.
 
seems that i remember from the 60's when i got a diver's card that using compressed air that wasn't delivered by a pump for air meant to be breathed could be dangerous because the wrong type of pump could also deliver oil into the compressed gas.
 
I remember that same warning when I got my dive card years ago. But numerous threads here and elsewhere have convinced me that bottled oxygen is bottled oxygen, the price of the product just increases when someone has to place an 'Aviation use only' sticker on it (kind of like the certified vs. experimental argument).
 
seems that i remember from the 60's when i got a diver's card that using compressed air that wasn't delivered by a pump for air meant to be breathed could be dangerous because the wrong type of pump could also deliver oil into the compressed gas.

Air and O2 are two very different things. With diving air, you had to worry about oil contamination from the compressor. Such a thing would take care of itself in the O2 delivery industry because any oil contamination would cause the compressor to explode long before it got to the customer?s bottle.....

I?ve been to to O2 plants - these days, they make one grade - far cheaper for them to make the highest grade than to have multiple production pipelines.
 
for those performing their own refills, is a single "big bottle" sufficient? I ask because many of the online parts providers push a cascading tank system.
 
I recently joined a group that shares a refill tank. The three tank setup helps ensure you get as much out of each tank as possible and can top off the airplane tank. We are looking for a third tank.
 
I recently joined a group that shares a refill tank. The three tank setup helps ensure you get as much out of each tank as possible and can top off the airplane tank. We are looking for a third tank.

We have a six tank group at the airpark - we split the cost of the daisy chain charging rig. It costs $40 to exchange a tank for a full one. My one tank investment has provided a half dozen refills of my rather large Mountain High AL-682 tank.

Carl
 
I have 2 large tanks cascaded and once in a while wish for a third (owned), but the refill cost is so dirt cheap I haven't messed with the 3rd tank.
 
Numbers to clarify . . .

We have a six tank group at the airpark - we split the cost of the daisy chain charging rig. It costs $40 to exchange a tank for a full one. My one tank investment has provided a half dozen refills of my rather large Mountain High AL-682 tank.

Carl

A JD tank has 18 person hours of O2 at 2200 psi.
A single K tank (249 ft^3) can "fill" a JD 6 times, diminishing the person hours each fill. Assumes the JD is empty - 300 psi, and using MH digital demand system at 15000'.
The 6th "fill" provides the JD 68% (13 person hours) of original full. It has provided 92 person hours of O2.


Economically it depends . . . . .
on - how much trouble, cost, time is takes to get an aviation tank filled. You can own more than one. If buddies are sharing -it gets better much more quickly. With a 3-K tank system, the "variable cost" of filling a JD becomes less than $2.

There is a cost for everything, but each pilots situation and expectations for fill are different. Assumptions change the results and conclusions.

Investment in the transfill hardware will vary - Personally, I would not use a transfill setup without proper gages any more than a hot-shot freon can from the grocery store. ("not that there is anything wrong with that") YMWV
 
for those performing their own refills, is a single "big bottle" sufficient? I ask because many of the online parts providers push a cascading tank system.

With a cascade system you will probably never be able to fill your bottles completely since the bottle you are filling increases the total volume of the oxygen, thus reducing the pressure. I think this is what PV=nRT means if I recall from physics class so many years ago...

With a compressor you will be able to get a full 3000 psi in the bottle every time.

It might not matter if you aren’t missing the full capacity on every flight. Just know what to expect.

Don
 
One other thing to keep in mind is that high pressure oxygen is not the safest gas to handle. Transfilling in particular requires that you keep everything very clean of hydrocarbons and debris as high pressure o2 will cause things to catch fire quite easily with much smaller amounts of heat than we are used to, explosively at times.

Transfilling is a great way to save a few bucks (maybe) and hassle but be aware of the risks and make sure your insurance will cover it if something happens.
 
I used to get free refills from a single big bottle, that was certainly more than sufficient. Then the bottle renter sold his Mooney and got a turbine. I filled a 'medium' bottle from his last big bottle to about 1300psi, it is still giving me 1000 psi fills on my Jumbo D, which with my pediatric regulator and conserving cannulas is plenty for two all the way, for example, to OSH and back on a single fill. About time to figure out how to get a proper fill somewhere.
 
Try a local scuba store, I've had great luck with cheap fills that way. $5 for aviation oxygen, $0 for emergency-use oxygen.
 
Read lots of articles and have been filling my own O2 since I bought it. I keep thinking I?ll buy a second large bottle for transfilling but I get so many ?almost full? fills and with my pulse demand system I haven?t found a Xc yet I?ve needed a fill.
 
Refill booster pump .

Great thread since I want to build my own system. As far as refilling from a large tank and getting a full fill as the source tank empties, has anyone used a small high pressure booster pump till the source tank is empty. I found very small pumps available from scientific supply houses that are oil free and seem like they could do the job. And what?s the ideal size of tank to use in a RV that will last a reasonable time?
 
A buddy of mine and I just leased two 180 cf tanks and set up a home fill station. He had the hoses made and bought a regulator and I got the tanks and cart. The tanks are $55 per year each and $25 each fill. I have a 48 cf tank and he has a 75 cf tank in his Mooney. It was super easy to do and we are guestimating about 6-7 fills out of the two tank setup. There are plenty of other folks on our field who run O2 and since the FBO doesn't fill, we may be able to recoup our yearly costs just from helping others out.

For me, it's worth the upfront costs since my field doesn't provide O2 fill ups. My MH system is built in so not an easy thing to pull the tank to take it to a dive shop (there are a few around in NC) each time I need it filled. But then again, my buddy and I both are DIYers!
 
I also fill at home.

Remember, compressed oxygen can injure the careless. No lubricant. Keep everything clean. Open and close valves slowly, and use a slow fill rate.
 
Great thread since I want to build my own system. As far as refilling from a large tank and getting a full fill as the source tank empties, has anyone used a small high pressure booster pump till the source tank is empty. I found very small pumps available from scientific supply houses that are oil free and seem like they could do the job. And what?s the ideal size of tank to use in a RV that will last a reasonable time?

Tom, this was my thought too. I researched O2 intensifier systems that used air pressure to operate the O2 side of the pump. They would pump to 3000 psi from 100 on the tank. There were no listed prices or advertisements, and the two companies found got quoted - they were around $5k but proven safe for the pressures and O2. NASA did lots of studies on oxidation rates of various metals and elastomers in high pressure O2 for the space effort 60+ yrs ago. It is a different world of science!!

If you have a more cost effective source for a pump, please share. Thanks
 
BillL;1278436) If you have a more cost effective source for a pump said:
I?ve found some on line for the 2 to 3 hundred dollar range from scientific supply
houses but their not very clear on the lubricant used in the unit. Any oils near pure oxygen are extremely unstable and self igniting. I remember very vividly a training film I saw years ago showing what happens when you just put oil on a oxygen regulator fitting to make it thread on easier. Nasty explosion. :eek: Cleanliness is of the upmost importance around oxygen.:)
 
Safety first

+1 on what Bill and Dan H. said here. I've been filling my own bottle from a single 180 cylinder for 11 years now. Works well for me, but you must be slow and careful to avoid a bad result.

On my new project I will be trying out the Inogen G4 concentrator. Weighs under 4 pounds and no backpack with an 8 pound O2 bottIe in the plane. I expect good results based on what I've learned from others who have tested these portable concentrators. I'll post my results here one day...soon, I hope.
 
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Having never filled one before I’m glad my buddy had. Even going slowly it produces a lot of heat to the filling tank!
 
Having never filled one before I?m glad my buddy had. Even going slowly it produces a lot of heat to the filling tank!

Cylinder should not get too warm and definitely not too warm to hold comfortably. When we fill 2L O2 cylinders for diving it takes around 15-20 min to keep the flow rate safe.
 
For those of us at sea level (Florida) who think this is a mountainous terrain thread, let me share a recent experience.

I bought my -10 in Phoenix and wanted to take a trip through Napa and Tahoe on the return leg. I knew I would need O2 so I bought a 22 cube bottle and cannulas. The system worked great as high as 17,500? and one full bottle got the wife and me home with some to spare. We now use it on any longer trips when above 8000? and find we arrive fresh and feeling much better.

The use of O2 has made traveling much more pleasant and less fatiguing than before. Try it and you will never want to go without.

Mark
 
Cylinder should not get too warm and definitely not too warm to hold comfortably. When we fill 2L O2 cylinders for diving it takes around 15-20 min to keep the flow rate safe.
Can you elaborate on this 15-20 minutes? I am aware of the concerns with "popping" or quickly opening a bottle, regulator failure, etc. But once everything's stable, I was not aware of any flow rate limitations on oxygen when transfilling.
 
I rebuilt and own a Rix 4800 psi scuba air compressor and I use it routinely for straight air diving. For anyone even thinking about O2 boosters, just forget it. High pressure compressors/boosters are not really a DIY thing - theres heap of training and knowledge you need not to kill yourself (and your nextdoor neighbor, blow up your house etc etc) and the cost/benefit just isnt there compared to a local refill or bank transfill as most are talking about.

No trustworthy new pure 100% O2 compressor/booster can be had for less than 5k, and all boosters require a high pressure source to run, above 2500 as I remember (but could be wrong) - so that means buying and maintaining a high pressure compressor as well as most bank gas usually wont be over 2500.

Even as a recreational divemaster (I dive/do training at least twice a month for a shop) its not even close worth my time/effort/money/risk to own such gear - not even the compressor I do own, but thats a different story.

Now if your a rebreather diver, well then youre more likely to already own the said compressor/booster gear but then youre rationalizing among two expensive death defying hobbies and you know what youre doing...or the Reaper will take you soon enough.
 
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Can you elaborate on this 15-20 minutes? I am aware of the concerns with "popping" or quickly opening a bottle, regulator failure, etc. But once everything's stable, I was not aware of any flow rate limitations on oxygen when transfilling.

The big risk with high pressure O2 systems is that seemingly normal things tend to explosively combust. You want to minimize the chance of that happening and reducing temperature of the transfer gas gives you a little bit more margin. Additionally, it reduces the velocity of the gas so gives you a bit more margin on any debris that may be in the system banging around and possibly sparking. Mostly you want things to be absolutely clean of hydrocarbons.

MH has a short page on some of the risks:
http://www.mhoxygen.com/component/attachments/download/427

NASA has done some fun studies showing metals like steel and brass combusting in high pressure oxygen. They were having issues during space shuttle testing with parts of the assembly catching fire. Yup, metal bursting into flame, crazy stuff :)
https://link.springer.com/article/10.1007/BF02833991
 
Can you elaborate on this 15-20 minutes? I am aware of the concerns with "popping" or quickly opening a bottle, regulator failure, etc. But once everything's stable, I was not aware of any flow rate limitations on oxygen when transfilling.

Someone else mentioned it, but its a PV=nRT situation - pass high pressure thru a small aperture and the temp rises. IOW youre generating heat as you transfill. Dial the pressure you fill down, and the heat generated goes down, and also has more time to dissipate into your surroundings.

O2 is especially temperamental wrt ignition, so you need to keep the heat out during transfer. Thats done by slow slow slow filling. I was taught that a warm cuddly scuba air tank is fine, but is considered too hot for an O2 tank. Hot uncomfortable tank=expect the worst. For O2, no warmer than your ability to tell that its warmer compared to other room temp tanks - again thats what I was taught in tri-mix gas blending class. Thats cautious enough to live another day.

The other thing I was taught with O2 transfilling is that you never set it and forget it - ie set some filling rate and walk away. You stay with O2, adjust your fill rate as necessary to moderate the heat and the process has your undivided attention during the fill - no conversations, no phone calls, no crossword puzzles, no whatever. Stay focused - shes a witch.

Filling time clearly depends on tank size so a small medical size might be 20mins given the above, dunno. Eitherway evaluating tank temp is the SOP, not tank size.
 
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For those reading this thread: just curious how many refills you go through a year? I live in NJ and fly about 150hr/year. I usually get maybe 3-4 refills a year.
I investigated getting a bank of large bottles, but it just isn't worth it to me. There is significant hassle in getting those large bottles refilled when the time comes, and I am much more comfortable getting a full refill when I get one.
The main thing driving me to want to be able to fill myself was so that I could always have a full bottle. I never know, on any given flight, if I will need O2 for weather or winds until just before or during the flight. A full bottle gives me options, just as a full fuel tank gives you options.
I have a home-made system with a Jumbo D tank. Refills at the medical store are $18. That is 6 hours of O2 use for my wife and I.
My solution was to buy a second O2 tank. They are on quick connections. If I have a 1/2 full bottle and think I will need more O2, I swap it out for the full one. If it is a short flight, I use the 1/2 full bottle. I have a card that shows me how many minutes of O2 flow I have available for every 200psi of tank pressure.
I laminated a copy of my O2 prescription to each bottle so I can always get it refilled on the road, if needed.
 
Will most medical supply places refill tanks for non medical (no script) use?

Not sure on medical supply places, but most bulk gas supplier will happily fill your bottle with Aviator Grade O2 with no script. I've found that there is an AirGas within driving distance of just about anywhere in the country ;) http://www.airgas.com/
 
Not sure on medical supply places, but most bulk gas supplier will happily fill your bottle with Aviator Grade O2 with no script.

My industrial gas supplier fills my medical O2 bottles with either a prescription or a pilot's license as proof of need. Got to have one or the other...
 
The heat I was talking about was just warm to the touch. I didn't really expect any heat but hadn't read that much into it yet. It did take us about 20 mins to fill and we stopped for a break half way through.

Certainly be careful and diligent.

You'll get mixed results with having a medical supply place refill a bottle. For us, refilling the large bottles are easy. We just swap the whole thing out on the way to lunch. $25 each tank.
 
My industrial gas supplier fills my medical O2 bottles with either a prescription or a pilot's license as proof of need. Got to have one or the other...

Take them a Repairman's Certificate next time, see if they get confused :)

We share a two-refill system that my buddies put together several years ago. Easy as pie, cheapest way to go, and we swap out the most empty tank by driving across the street to Airgas to drop it off and pick up a full one. Serves 4 or 5 of us very well, and none of that nonsense with "proof of need" or other BS.

BTW, all O2 from suppliers is the same (hashed to death on these forums already).
 
Here's a picture of my transfill setup. I rent these from a local welding place for $6/mo for the pair. Refills are $26. I've filled a 22cf cylinder 6 or 7 times and still get full pressure with this arrangement. Haven't yet needed a refill in the year or so I've been using it. The 22cf Jumbo "D" cylinder in the plane supplies plenty of O's for 4 of us when cruising up high in the -10 and fits nicely between the rear seats.

i-5kvFRn2-M.jpg


i-9FVsp7K-M.jpg
 
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